Device for recording vapor pressure



Aug. 9, 1938. s. s. SMITH 2,126,052

` DEVICE FOR RECORDING vAPoRdREssURE K v original Filed ned, 29, 1930 2 sheets-sheet 1 Aug. 9, 1938. s 's SMI'TH 2,126,052

DEVIOE FOR RECORDING VAPOR PRESSURE originai Filed Dec. 29, 1930 2 sheets-sheet 2 from Patented Aug. 9,

UNITED s'rATEs DEVICE FOB RECRDING VAPOR PRESSURE sydney s. smith, st. Louis, Mn., mignon, by mesne assignments, to Floyd L. Hallam, Los

Angeles, Calif.

Original application December 29, 1930. Serial No. 505,453.4 Divided and this application October 29, 1935, Serial No. 47,338

8Clalms.

This application is a division of my application Serial No. 505,453 iled December 29, 1930and subsequently issued into Patent No. 2,073,908 on March 16, 1937.

Une of the objects of my invention is to providemeans for continuously recording the vapor pressure oi a liquid product foi' example, the iinal end product of a rectier system.

One of the uses of this invention is in the lo reciiication of gasoline. Probably the most characteristic quality which gasoline has is its vapor pressure and is something which may be mechanically recognized and by which regulating equipment may he actuated.

apparent from the following detailed description takenin connection with the accompanying drawings. in which- Fig. l is a diagram of a rectifying system includ- 2@ ing this invention.

Fig. il is a side elevation partly in section of a double diaphragm pilot valve 2 shown diagrammanually with its connections in Fig. 1.

Fig. 3 is a side elevation partly in section of a 2h diaphram relief valve 3 shown diagrammatically with its connectionsin Fig. l.

Fig. 4 is a detailed cross section oi a. trap 4 which constitutes apart of a pressure bomb and which is shown diagrammatically with its connec- 30 tions in Fig. l.

It is to he understood that this invention relates to controlling rectification or the operation of a rectiher column and the particular construction and arrangement ci the rectifier itself is of no importance. A typical rectiier system is illustrated and described but it is to be understood that this is merely an exempliiication and the apparatus consiituting the subject matter of this invention may he used in connection with rectiiier columns dihering materially in construction from that which is illustrated and described.

h rectier column 5 has a. kettle 6 which is heated hy steam introduced through a pipe l, the spent vapor passing out through a pipe 8. Steam may he introduced into the pipe 'l from a pipe El by means oi a valve I0, automatically con-I trailed from a thermostat unit Il having a pipe connection l2 with the interior oi the column 5, or it may be controlled manually by a valve I3 in a hy-pass lil. A condenser l5 is cooled by Water passing into it from a. pipe l1 and out through a pipe it. A connection I8 with the interior of the column near its top provides means whereby cooling water flowing into the condenser may be 55 automatically regulated through a thermostat The specinc objects of the invention will be (Cl. 'I3-50) valve and unit, not shown but well understood in the art. Connections I9 and 20 with the interior of the rectifier column provide means whereby pressure and temperature recorders may be connected for indicating or recording the pressure and temperatures in the column. The nal end vapor product may be withdrawn through a pipe 2|, and the nal end liquid product may be withdrawn through a pipe 22. The raw product to be rectified, such as raw gasoline, may be introduced on various plates of the rectifier column through a pipe 23, the connections with the various points being regulated by valves 26.

The run down of the nal end liquid product may be regulated by valves 25 and 26, one of which is usually regulated automatically by means not shown but which is well understood in the art. The operation of the rectifier is controlled ,by regulating the discharge of the top product through the pipe 2l, for by so regulating this discharge it is obvious that the pressure in the column will be controlled. Atypical rectifier column has been described and now the novel means for controlling the operation of such a rectiiier column will be described.

It consists, as forecast, of means for automatically regulating the discharge of the final end vapor product in accordance with the column pressure and the vapor pressure of the bottom product. It consists primarily of a valve 3 in the pipe 2 l. As illustrated this valve is of well known construction and is not of itself novel. It comprises a. housing 2l in which are situated valve seats 28 for cooperation with valve discsr29 secured to and operated by the stem 30, which stem is secured to a diaphragm 3l. A compressible spring 32 is positioned about the stem 3|) in such a manner as to normally close the valve by bringing the discs 29 against their respective seats 2B. The diaphragm 3l is situated in a chamber 33 having a connection 3l `with a source of liquid pressure which, as will hereafter be described, is regulated in accordance with the column pressure and the vapor pressure of the final end liquid product.

The iiuid pressure introduced through the connection or pipe 3l is regulated by the pilot valve 2. The valve 2 includes a stem 35 to which is secured diaphragms 36 and 3l. The diaphragm 3E is situated in a chamber 36a. which has a pipe connection 38 leading to and communicating with the interior of the rectifying column, and, therefore, the diaphragm 36 is responsive to the column pressure. The diaphragm 3l is situated in a chamber 39 having a pipe connection 4D connected with means for securing a constant vapor which will be disclosed later in detail. A Pipe 4I communicates with a source of constant pressure, not shown, and the reciprocation of the valve stem 3l permits a iluid under such constant pres--v sure from the pipe 4I to bel impressed through the pipe 34 on the diaphragm 3l of the 4control relief valve 3. A pipe 42 permits the relief of such pressure from the diaphrgamchamber 33 'in a manner which will presently be described.

The pipe. 4| communicates with a: chamber 43 in which is situated the ball 44 having aseatt and normally pressed outwardly against its seat by-a spring 4I. The ball 44 is pressed downwardly by action of the stem 35 against a ball 41 and a iloating member 43. The pipe 34 communicates with a chamber 43 which is in communication with the chamber 43 through a passage between the ball 44 and its seat 45. 'Ihus the passage between the pipe 4i communicating with the source of constant pressure and the pipe 34 leading to the diaphragm chamber 33 is controlled by the reciprocation of the hall 44, which reciprocation is caused by operation of the valve stem 35. The pipe 42 communicates with a chamber which has a passage to the chamber 49 controlled by the ball 41 and its seat 5|. As the valve stem 35 rises the ball 41 is lifted from its seat at the same time the ball 44 is positioned on its seat, thereby closing the communication between the pipe 4l and the pipe 34, and opening communication between the pipe 34 and the pipe 42. It is to be understood, of course, that the pipe 42 is open to atmosphere.

A compressible spring 52 is positioned to move the stem 35 upwardly in a direction contrary to the movement of the stem .when iniluenced by pressures on the diapragms 36 and 31.

Itis to be understood, therefore, that excessive pressures on the diaphragms 35 and 31 cause the valve stem 35'to be moved downwardly opening communication between the pipe 4I and the pipe 34, thus causing a pressure to be exercised on the diaphragm 3| of the relief valve suilicient to open the valve 3 relieving the pressure on the rectifier column. When the pressure has been suiliciently relieved the spring 52 will cause the, stem 35 to move upwardly closing communication between the pipe 4| and the pipe 34 and opening communication between the pipe 34 and the pipe 42, thus venting the chamber 33 to atmosphere and causing the spring 32 to close the valve 3. It will be seen, of course, that so far as principle is concerned the apparatus might work just as well if the valve stems 35 and 30 were integral, thus operating the valve 3 directly by the operation of the diaphragms 36 and 31, but the pilot type of valve is preferred since much ner control may thereby be obtained.

I prefer to make the diaphragm 36, which is responsive to the column pressure, smaller in area than the diaphragm 31, which is responsive to the vapor pressure of the end liquid product. I prefer to make the area of the diaphragm 31 about two and one half times that of the area of the diaphragm 36. In rectifying gasoline typical pressures may be 125 pounds column pressure on the diaphragm 36 and a vapor pressure of 200 to 250 pounds per square inch on the diaphragm 31.

The vapor pressure of the nal end product is obtained in a pressure bomb 53 including the trap 4 to which is connected the pipe 4l. A pipe I4 connects with the pipe 22 containing the run down and with a coil 55 within the bomb I3. The bomb is heated by steam from a pipe 56 includes achamber 53 having anv outlet I3 controlled'b'y a valve 6l Voperated by a iloat 3l. The

'run down product is'introduced into the coil II from the pipe 54,15 hemd by mam, and una caused to impress its vapor pressure through the pipe 4l on the .diaphragm l31 and on the pressure recording gauge 32. 'lhis gauge 32 is of the well .known double pressure recording type, the other pressure being recorded being the pressure in the column transmitted through line 33 as will .be seen from the drawings.

Fromthe foregoing description it will be ob vious that the objects of the invention have been obtained.

Parts of the invention may be used without the whole and various changes may be made in the details of construction, within the scope of the appended claims, without departing from the spirit of this invention.

I claim as my invention:

1.' Apparatus for recording the vapor pressure of a liquid comprising a coil in communication with a source of said liquid, means for keeping said coil under a 'constant temperature, a trap in communication with said coil, an outlet from said trap, a vapor conduit leading from the trap above the level of liquid therein, and a pressure recorder connected to said conduit.

2. Apparatus for recording the vapor pressure of a liquid comprising a coil in communication with a source of said liquid, means for keeping said coil under constant temperature, a closed vessel in communication with said coil, a liquid outlet from said vessel, liquid level control means in said vessel in communication with said outlet, a vapor conduit leading from said vessel above the liquid level therein and a pressure recorder connected to said conduit.

3. Apparatus for recording the vapor pressure of a liquid comprising a coil in communication with a source of said liquid, a trap in communi cation with said coil, a constant temperature bath surrounding said coil and said trap, a liquid .outlet from said trap, a vapor conduit leading from said trap and above the level of liquid therein and a pressure recorder connected to said conduit.

4. Apparatus for recording the vapor pressure of a liquid comprising a coil in communication with a. source of said liquid, a trap in communication with said coil, a pressure vessel surrounding said coil and said trap, means for admitting steam to said pressure vessel, a liquid outlet from said trap, a conduit leading from said trap and above the liquid level therein and a pressure recorder connected to said conduit.

5. Apparatus for recording the vapor pressure of a liquid comprising a conduit in communication with a source of liquid, a trap in communi-I cation with said conduit, a constant temperature bath surrounding said trap, an outlet from said trap, a vapor conduit leading from the trap above the level of liquid in said trap, and a pressure recorder connected to said trap through said vapor conduit.

6. Apparatus for recording the vapor pressure of a liquid comprising a coil in communication with a source of liquid, a closed vessel in communication with said coil, means for maintaining said coil and vesel at a constant temperature, a

liquid level control device in association with 13 a pressure recorder communicating with the vapor space of said container.

8. Apparatus for ascertaining the vapor pressure of a continuous liquid sample. comprising a container in communication with a source of 5 said liquid and having a vapor separating space, means for keeping said vapor separating space under constant'temperature, a liquid outlet from said container, a fluid pressure gage, and means connecting said gage with said vapor the container.

SYDNEY S. SMITH.

space of 10 

